Trygve Magnus Haavelmo (13 December 1911 – 28 July 1999), born in Skedsmo, Norway, was an economist whose research interests centered on econometrics.

Haavelmo was Frisch's assistant for a period of time until he was appointed as head of computations for the institute.

[citation needed] He was a professor of economics and statistics at the University of Oslo between 1948–79 and was the trade department head of division from 1947 to 1948.

Haavelmo acquired a prominent position in modern economics through his logical critique of a series of custom conceptions in mathematical analysis.

[citation needed] Judea Pearl wrote "Haavelmo was the first to recognize the capacity of economic models to guide policies" and "presented a mathematical procedure that takes an arbitrary model and produces quantitative answers to policy questions".